effect of infrared and functional appliance treatment on mandibular growth in rabbits

Mandibular retrognathisim is one of the most common problems in orthodontics and dentofacial orthopedics. Many treatment techniques involve enhancing mandibular growth using functional appliances [FA] in growing patients. The effect of these functional appliances is still controversial. Infrared [IR] is known to enhance tissue healing by increasing metabolism and mainly due to its thermal effect. The purpose of this preliminary study was to investigate the effect of using IR alone or in combination with FA to enhance mandibular growth in rabbits. Five growing male white New Zealand rabbits were chosen and treated with IR and FA or IR only at different treatment times. The results show that IR can stimulate mandibular growth especially when it is accompanied by FA. The IR effect is, however, dose dependent. The results of this preliminary study suggest performing a larger study using different treatment doses and statistically determined sample size

Maxillary anterior segmental advancement by distraction osteogenesis

Previous researches have shown that distraction osteogenesis is a useful technique that provides many advantages over the regular orthognathic surgical procedures. Treatment of skeletal Class III due to maxillary deficiency in adults usually requires maxillary advancement with complicated orthognathic surgical procedures that in most cases requires extraction of upper first premolars to decompensate the proclined upper incisors. The aim of this study was to evaluate the skeletal and dental changes after using intraoral tooth-borne osteodistraction appliance with acrylic base that is cemented on the teeth to advance the anterior segment of the maxilla in patients having Skeletal Class III due to maxillary deficiency. Distraction osteogenesis was performed after two vertical osteotomies distal to lateral incisors and a horizontal osteotomy that connected the two vertical osteotomies, just 5mm apical to the roots of the maxillary incisors. Distraction started three days after the surgical osteotomies at a rate of 0.75 mm/day and continued for average of 8 +/- 3 days based on the pre-planned treatment for each patient. The clinical records that included study models and lateral cephalomteric radiographs were obtained before and after distraction of the anterior part of the maxilla. Model analysis indicated increased arch perimeter after distraction osteogenesis by 7.6 +/- 0.75 mm and cephalomteric analysis indicated improved patients profiles after osteotomy [increase in ANB angle 6.3 +/- 3.14 degrees]. The obtained arch length was used to correct [decompensate] the axial inclination of the proclined upper incisors due to the pre-existed skeletal problem or to relief maxillary anterior pre-existing crowding. In Conclusion: the presented technique could be performed easily on an outpatient setting and using a very low cost custom made distraction devices without the need for premolar extraction for de- compensation of the proclined upper incisors in skeletal Class III due to maxillary deficiency

effect of anteroposterior position of the chin on profile preference in a Middle Eastern population

The influence of the anteroposterior maxillomandibular relation oil preference is controversial and is affected by ethnic background. The objectives of this study were to evaluate the perception of profile preference in a Middle Eastern population [West side area of Saudi Arabia] and to test for differences in profile preference among various dental professionals [including Orthodontists, Oral and maxillofacial surgeons, and general dentists] and non dentists. The original null hypothesis was that no difference will be detected in profile preference between among dental professionals and non dentists. To test the null hypothesis, two profile photographs of males and others of females [one for adolescent and the other for adult for both [lenders] obtained from the record of Arabic orthodontic patients that had balanced facial profiles were chosen. The photographs were manipulated using Adobe Photoshop computer software to produce five different profiles for each patient representing five profiles from severe prognathic to severe retrognathic profiles. A survey was made to test for profile preferences among the different groups [each group consted of [30 judges] using a live-point likert scale with a rating scale of 5 [most preferred] and 1 [least preferred]. The difference in profile preferences among groups was evaluated using ANOVA test. Results showed all judge groups preferred straight profiles for both males and females. No statistically significant difference was shown between the judge groups in most profiles tested, however orthodontists and lay persons preferred slightly concave female profiles than oral surgeons or general dentists. In contrast, oral surgeons preferred slightly concave profiles than straight ones for males In conclusion, Straight profiles were the most preferred, even there were few significant differences between judges regarding convex or concave profiles. The obtained results should be considered when planning orthodontic and orthognathic treatment in the Middle East population